I was wondering if someone with some engineering/physics know-how and experience could confirm something for me. Is it better to tie down a rectangular carport structure (10' x 20') with lines that extend outward (say, at 45 degree angles) from the corners? ...thus increasing the overall footprint of the structure? Or could it be equally secure if you tie with lines that crisscross flush along the sides (in an X formation, leaving one opening to easily walk through)?

I'm thinking it is better with some lines extending out at angles because you're trying to anticipate the wind blowing from multiple directions, changing direction quickly, etc. The more lines the better. But I am hoping to not take up an excessive amount of space within my camp.

Timezone LaFontaine wrote:I was wondering if someone with some engineering/physics know-how and experience could confirm something for me. Is it better to tie down a rectangular carport structure (10' x 20') with lines that extend outward (say, at 45 degree angles) from the corners? ...thus increasing the overall footprint of the structure? Or could it be equally secure if you tie with lines that crisscross flush along the sides (in an X formation, leaving one opening to easily walk through)?

I'm thinking it is better with some lines extending out at angles because you're trying to anticipate the wind blowing from multiple directions, changing direction quickly, etc. The more lines the better. But I am hoping to not take up an excessive amount of space within my camp.

if we arn't worried about the structure being lifted and carried away by the wind, but we are worried about the force of the wind on the stucture then...

[quote]When designing a building for lateral loads such as those generated by wind or earthquakes, a design engineer may have several alternatives. Lateral loads may be transferred to the foundation via braced frames or rigid frames, diagonal rods or "X" bracing, including let-in bracing in the ease of wood frame construction, or other methods. Where structural panels are used for the roof, floors, or walls in a building, lateral loads can be accomodated through the use of these ordinary vertical load-bearing elements. This type of construction is easily adaptable to conventional light frame construction typically used in residences, apartment buildings and offices. The same concept is equally adaptable to larger warehouses and similar industrial or commercial buildings.

A diaphragm is a flat structural unit acting like a deep, thin beam. The term â€œdiaphragmâ€

Generally, the wind blows from one direction, sometimes reversing itself. I tried an X in the inside of the shade, but it didn't work because the wind lifted from the outside, and nothing secured against that lift. (Am I making sense?)

Louise and I have a 10x10 peaked-roof shade with side flaps, one of which is on the windward side of the predominant wind direction. We tape our legs to rebar, and that has held for the last few years.

If I may add my two cents after having done this for ten years on the playa. Put up your shade structure, duct tape all of the pieces that fit together, hammer in about a 3' rod of rebar down about 14 inches, then duct tape the shade sturcture onto the rebar. Use guy wires for the front and back (make sure you have something on the end of rebar that they are attached to; we recommend the heads of Barbies broken off of the body of the doll, but then again, that's just us) then you should be just fine. There are few, if any, problems structurally on the playa, that: duct tape + rebar + more duct tape + absinthe will not handle.

We've had a 10x20 carport last year, which was secured with rebar and ductape on all 8 legs. Nothing else. It held thru all the storms. It was up on Friday before the event, so it went thru the weekend storms as well as the one on Monday.

It was also still up on Sunday night, and it made it thru the storm after the temple burn without issues. There was a lot of shaking going on that night, but the rebar held like a charm.

Thanks for the tips, y'all! I hadn't thought of ducttaping the joints of the metal structure itself.

For setups with guy lines, how do you tie the lines to the stakes? Are you bending the rebar like a narrow staple and sinking both halves? Or using something similar to a turnbuckle? Any special kind of knot?

AntiM, I had seen you mention having the carport tipped over before and was thinking of doing the same thing, in part because it ends up having a somewhat more aerodynamic form. I was just curious what the resulting height is. I'm 6'6"... I don't plan on spending a whole lot of time in there standing around but it could end up being a hassle if I am having to be stooped over all the time when getting dressed, etc. I was also hoping to hang a solar shower bag from one of the central bars.

Larry doesn't have to duck, but he's only six-one. I'm short, so it suits me. I think it may not work for a tall person! The shade in between the two is a pop-up without the canopy, just doubled camo netting and attached to the carports. Very cozy.

Our rebar has been welded into T shapes, and the tie down ropes are spliced into an eye at one and with a simple tightener at the other. These are only used for the carports, very specialized. The back of the carport has special stubby legs Larry made from an old trampoline frame., they fit into the feet that came with the carports. Those tie-downs run straight down each leg.

Our carports are from Sam's Club, 2003. I think the legs/beams are larger and heavier than the new carports.

I bent all my rebar in a candy cane one year and found it was too hard to pound in the ground straight with the round top. I ended up taking it to a recycler. I use straight rebar now cause it pounds in easier. I cap it with an actual rebar cap or something like it. I usually tape that on with gaffers tape.

I swear by staking down at a 45 degree angle for both the rebar in the soil and the guy line from the top of the structure. The rope or twine is always at a 90 degree angle to the stake when tied on. I also never attach a tarp or shade cloth directly to a stake. I always use a lanyard at least one foot in length. This seems to act as a shock absorber and things stay put better for me that way. I have had tarps and shade cloth pull stakes out of the ground when attached directly to the stake through a grommet.

I also swear by bailing twine. The orange stuff that comes in rolls that are super long and a little expensive. It takes knots really well and has good tensile strength. One roll lasts me for 3 years using it at home and at the burn. Available at any agricultural supply store.

An engineer friend told me it is not the wind that actually pushes a structure over it is the low pressure area developed behind the structure that pulls the structure over in to the vacuum. He stated it in a way that the low pressure area was of more concern than the actual pushing of the wind. Either way staking on the windward side for whatever way the wind is blowing is necessary.

Black Rock City Welding and Repair. The Night Time Warming Station.

When you pass the 4th "bridge out!" sign; the flaming death is all yours.-Knowmad-

Its best to secure to the largest vehicles possible. Ideally one would have 4 denied art cars and one approved mutant with flame effects in camp. This would help make sure you don't accidentally leave some rebar and kill some other lunatic that goes there for other lunacy at another time.

Don't be a lunatic.. evolve.. use art instead of rebar.

(just make sure its really really heavy art)

PS I am proud to be a lunatic.. but I can't afford tanks so I gotta try and tie to someone elses car or truck

motskyroonmatick wrote:An engineer friend told me it is not the wind that actually pushes a structure over it is the low pressure area developed behind the structure that pulls the structure over in to the vacuum. He stated it in a way that the low pressure area was of more concern than the actual pushing of the wind. Either way staking on the windward side for whatever way the wind is blowing is necessary.

No doubt... a sixty foot dia. dome eggshelled in a wind storm in 2000. Manufacturer thereafter went to 1" conduit rather than 3/4".

I saw it after the failure, when the wind was still causing the thing to lift up and pound on the ground, so inadequate staking obviously was a big factor.

Goddamn it Sail Man, this year our art car, I'm sorry, mutant vehicle, will be approved! We've stripped off the ties, taken off the mosaic off the hood, will repaint and then completely redesign the vehicle. You won't be able to recognize it. Barbie's Mobile Whorehouse. Um, I'm looking for volunteers. I mean, what's a whorehouse without.......

Gotta say, I'm more of a bungee cord or zip-tie guy than a duct tape guy when it comes to securing rebar to structures. But I hear you about taping the various pvc/steel supports together. A suggestion for those who are using duct tape: Gaffer's tape is just as strong, but leaves much less (if any) gunky residue behind. Easier to deal with. It's more expensive than duct tape, though. I know my local Guitar Center has it. Or surely you can find it online somewhere.

[quote="SonOfUgly"]i had a 10' x 20' car port and used metal T fence post tied and taped to the legs of it and the winds did nothing to it[/quote]

sorry? wha? You took a metal T fence post and tied what and what to where? And how? Can you please describe more clearly what you're talking about?

Sorry if I sound like a crank, but I see a lot of this in otherwise potentially-helpful posts here: Without the availability of diagrams, you have to use pretty descriptive terms and a bit of detail to help people understand what you're talking about.

SonOfUgly wrote:i had a 10' x 20' car port and used metal T fence post tied and taped to the legs of it and the winds did nothing to it

sorry? wha? You took a metal T fence post and tied what and what to where? And how? Can you please describe more clearly what you're talking about?

Sorry if I sound like a crank, but I see a lot of this in otherwise potentially-helpful posts here: Without the availability of diagrams, you have to use pretty descriptive terms and a bit of detail to help people understand what you're talking about.

T posts might be over-kill, I use 24-36 inch metal concrete form stakes for the past 10 years without a problem.( drive in about 12 inches) either way here's the deal.

If your using a carport, build the carport. Set the stake/post next to the leg of the carport. Drive the stake/post into the Playa(you can move the leg to allow you to drive the stake/post in) I set the stake at a slight angle to accommodate the foot of the carport leg. I then use good Duct tape and wrap tight around both at the top, middle and bottom. Tape the top of the stake/post to keep campmate from ripping skin off if they walk to close. Now some here wrap saran wrap 1st around the carport legs to keep the duct tape from leaving a mess. I don't, but you can if you want. I don't use any guy string ect ect. Never have. If you use carpet, just drive the stake/post right though.

To remove round stakes, use a good pair of "Vise Grips" Clamp tight and twist while lifting.. Easy to do.
T-post on the other hand are much heavier and harder to remove. You bend then back and forth( rocking) to enlarge the hole and lift out. They do make a t-post remover if you plan on using a-lot.

T-post puller being used with a hi-lift jack. This requires no effort to pull the otherwise stubborn T-post. A couple years a go, we tried pulling the posts, using a 4x4 as leverage. The 4x4 eventually broke in half...probably because it was old and dried out, but they are NOT easy to remove unless you have the right tools.
Yes they are heavy, but you can walk away from your structure without worrying about it being blown away. Duct taping the pipe joints of the frame is also good. I learned that trick on my first night at Burning Man in 1999.. We had gusts of wind recorded over 100mph.

also...we used 1 inch conduit, in the same fashion as the t-posts. They were easy to drive, and remove, but after a couple days..started coming out of the ground.

Sometimes it is tough to get a sense of what will work without some pretty descriptive language. As I suck at that, I'm putting up a picture instead.
Well, I would if I could figure out how to do it. Grrr...

ANYWAY.... the link takes you to the pic of a shade tent I bought on ebay last summer (planning way ahead for this year's Burn). My questions for any of you well seasoned, simmered and stewed Burners out there are:

1) Should I be staking with rebar at each of it's six points on the ground AND attaching the interior pole to rebar with zip-ties/gaffer tape/duct tape?
2) Is it worth even trying to create some sort of attachable/detachable covers for the 3 zippered screen doors and three half "windows" to try to keep dust down, or am I better off just letting it blow in, blow out at will?

Save the image to your drive with a right-click on it, "save image as...". Use a site such as photobucket to upload it, then copy and paste the link the site will give you with image tags on either end.

that looks like a big ol sail to me... your DEFF. going to have to stake it down. Might go with bent re-bar at all the corners.. see how that goes..take extra rope, duct tape , & rebar with you. & a small shovel & vice grips & a boy to remove the re-bar later..

I thought staking all round would be called for. I'm thinking 24" rebar? I was hoping with so much air flow through the mesh openings, it would be less likely to catch too much wind and take flight.
As for the removal later, I try not to go anywhere without extra rope, vise grips and a boy.